How to diagnose hypogonadism?

The diagnosis of hypogonadism (also known as testosterone deficiency or low testosterone) requires the presence of characteristic symptoms/signs combined with low testosterone levels.1-7 Symptoms of hypogonadism resemble those of aging; as a consequence, hypogonadism is often overlooked. To prevent this, clinical guidelines have developed diagnostic procedures to confirm hypogonadism in a patient who has symptoms and/or signs of testosterone deficiency, which are summarized below.1-7 These include symptomatic evaluation, medical history, physical examination and measurement of testosterone levels.

    Symptomatic evaluation

    Evaluation of symptoms that may be related to low testosterone is mandatory for making the diagnosis of hypogonadism. Use of validated symptom questionnaires, such as the Aging Males’ Symptoms (AMS) questionnaire is helpful in daily clinical practice for symptomatic evaluation. The AMS can be used both as part of the diagnosis, and for monitoring of symptomatic improvement during testosterone therapy.

    The most common and reliable symptoms of hypogonadism are sexual symptoms.8 These include reduced or absent libido, erectile dysfunction, difficulty achieving orgasm, reduced intensity of orgasm, and reduced sexual sensation in the genital region. Common non-sexual symptoms include fatigue, lack of energy, decreased vitality, inability to perform vigorous activity, depressed mood, irritability, “brain fog” (memory problems, a lack of mental clarity, inability to focus), and decreased motivation. These symptoms may occur singly or in any combination. Decreased libido is one of the primary symptoms of hypogonadism. It may occur, with or without any of other symptoms or signs, and is strongly suggestive of hypogonadism in men >50 years without obvious other causes, such as relationship issues and stress. Increased probability of low sexual desire, poor morning erections, erectile dysfunction and reduced physical vigor is seen with testosterone levels below 13 nmol/L (370 ng/dL),8 however, these symptoms can also occur in men with higher testosterone levels.

    Medical history

    Chronic diseases, such as type 2 diabetes and heart disease, are associated with low testosterone. Furthermore, certain medications, especially opioids,9-12 selective serotonin reuptake inhibitors (SSRIs),13 statins,14-16 and glucocorticoid medications 17,18 reduce testosterone levels. Therefore, comorbid conditions must be comprehensively investigated in every patient. Acute illnesses are associated with the development of functional hypogonadism; in patients with acute illness, measurement of testosterone levels should be postponed.